Since light-emitting diodes become able to generate high outputs in recent years, a white LED light source using a light-emitting diode (LED) is widely used to emit white light.
In particular, such white LED light source may be applied to illumination apparatuses which are requested to generate high intensity, to projector apparatuses and backlights for large-scale liquid-crystal displays. For the uses, since the white LED light source has merits that it is mercury-free to have small environmental load, it is excellent in color reproducibility, it is excellent in responsiveness, it can vary intensity and that it is long in product life, a white LED light source is expected as a white light source instead of related-art fluorescent lamps (hot cathode tube and cold cathode tube).
In order to save energy, that is, to improve efficiency in the above-mentioned white LED light source, it is important not only to improve luminous efficiency of the light-emitting diode itself but also to improve efficiency at which light can be emitted from a light-emitting diode chip.
The efficiency at which light can be emitted from the light-emitting diode chip is greatly influenced by assembly members located around the light-emitting diode chip.
Specifically, in order to improve light emitting efficiency, it is necessary to contrive assembly members located around the light-emitting diode chip.
As forms for connecting the electrodes on the substrate to the light-emitting diode chips, there may be a form in which the light-emitting diode packages are arrayed on the substrate, a form in which the light-emitting diode chips are directly mounted on the substrate and connected to the electrodes by wires or the like and a transparent resin is further formed to cover the light-emitting diode chips to seal the light-emitting diode chips (see Patent Document 1 and Patent Document 2, for example) and the like.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 10-294498
[Patent Document 2]: Japanese Unexamined Patent Application Publication No. 61-144890